04.08.03
3 p.m. CDT, Tuesday, April 8, 2003
Expedition Six CrewSTATUS REPORT: ISS03-15
INTERNATIONAL SPACE STATION STATUS REPORT #03-15
Expedition 6 Commander Ken Bowersox and NASA Science Officer Don
Pettit reconfigured critical power cables and continued the external
outfitting of the International Space Station today during a 6 hour,
26 minute spacewalk designed to complete a number of get-ahead tasks
for future ISS assembly.
Taking advantage of the final days of a three-man presence on the ISS
before the new Expedition 7 crew is launched, Bowersox and Pettit
began the second spacewalk of their increment at 7:40 a.m. CDT (1240
GMT). It was the second spacewalk for both Bowersox and Pettit, the
51st spacewalk for ISS assembly and maintenance and the 17th
spacewalk staged from the U.S. Quest Airlock. Flight Engineer Nikolai
Budarin helped the crew suit up and monitored ISS systems from inside
the Destiny Laboratory during the excursion.
Bowersox and Pettit set out immediately to set up tools and tethers,
and quickly went to work on separate tasks. Bowersox reconfigured
electrical connectors at the interfaces between the Starboard Zero
(S0) Truss and the two trusses flanking it, the Starboard One (S1)
Truss and the Port 1 (P1) Truss. The connector work will insure that
additional protection is in place to prevent the inadvertent release
of the truss segments from the S0 Truss through the trusses’
Bolt Bus Controller system. Bowersox also inspected a faulty heater
cable on the P1 Truss Nitrogen Tank Assembly but found nothing
unusual.
While that work was being conducted, Pettit replaced a power relay box
in the Mobile Transporter railcar system, which has experienced some
electrical problems in recent weeks.
Both spacewalkers then made their way to the Z1 (Zenith One) Truss,
where they successfully rerouted power cables to two of the four
Control Moment Gyros (CMGs) that provide orientation control for the
ISS from the U.S. segment. One CMG failed almost a year ago, and the
cable reconfiguration to CMGs # 2 and 3 will prevent both from being
disabled in the unlikely event a power failure occurs. The ISS can be
properly oriented with just two CMGs in operation. A replacement for
the failed CMG will be flown to the ISS and installed on the first
post-Columbia shuttle mission, STS-114.
Bowersox and Pettit pressed ahead to install two so-called Spool
Positioning Devices on fluid quick disconnect lines for the heat
exchanger on the Destiny Laboratory. The devices help keep internal
seals and moving parts from experiencing internal leakage as ammonia
flows through the station’s cooling system.
With that completed, the two station crewmembers ventured to the S1
Truss to secure a thermal cover on the truss’ Radiator Beam
Valve Module, which controls the flow of ammonia to the truss’
heat-rejecting radiators.
One final task awaited Bowersox and Pettit --- the deployment of a
balky light stanchion for the handrail cart on the S1 Truss that
would not unfurl during the previous spacewalk by the two crewmembers
in January. The stanchion proved to be just as stubborn this time,
but Pettit used a hammer to tap the stanchion free from its stowed
position on the 10th try. A light was then installed on the
stanchion, giving the truss the illuminating capability it needs to
assist future spacewalkers.
With all of their work completed, Bowersox and Pettit retrieved some
tools for future spacewalks from external locations and returned to
Quest to complete their spacewalk at 2:06 p.m. CDT (1906 GMT).
The crew will spend a quiet day tomorrow relaxing before resuming its
complement of scientific research and routine maintenance work on
board the ISS Thursday.
Meanwhile, Expedition 7 Commander Yuri Malenchenko and Flight
Engineer/NASA ISS Science Officer Ed Lu completed final preparations
before traveling to the Baikonur Cosmodrome in Kazakhstan tomorrow
from their training base in Star City, Russia to inspect the Soyuz
TMA-2 vehicle in which they will be launched on April 26 to begin a
six-month mission on the ISS.
Information on the crew's activities aboard the space station, future
launch dates, as well as station sighting opportunities from anywhere
on the Earth, is available on the Internet at:
http://spaceflight.nasa.gov/
Details on station science operations can be found on an Internet site
administered by the Payload Operations Center at NASA's Marshall
Space Flight Center in Huntsville, Ala., at:
http://scipoc.msfc.nasa.gov/
The next ISS status report will be issued on Friday, April 11, or
sooner if events warrant.
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